Applying ample grease to the tap (esp. in the vertical grooves) will help capture any shavings. I did mine this way with the manny in-situ, didn't find any shavings left in the tapped hole.

I'd also suggest tapping just deep enough for the grub/set screw to bottom out tightly with its head flush with the carb mounting face, rather than tapping it all the way down, then clean the threads with solvent and insert the screw with a hi-temp thread sealant (e.g. Permatex 59214 or 59235).